<!DOCTYPE html>
<html lang="zh-cn">
    <head>
        <meta charset="UTF-8">
        <title>study</title>
        <style  type="text/css">
            p:nth-child(2n+1){
                background: #009900;
            }
            p:last-child{
                background: #2E2E2E;
            }
            p:nth-of-type(4n+1){

                background: #0066cc;
            }
            p:after{
                content: '111';
                background: #0066cc;
                border: 1px solid red;
                width: 100px;
                display: block;
                float: left;
            }
            P:before{
                content: 'before';
                background: #00FFFF;
            }
            legend {
                display: block;
                margin-right: 100px;
            }
        </style>
    </head>
    <body>
        <fieldset>
            <legend>
                <button style="width: 80px"> 查询</button>
            </legend>
            <input/>
        </fieldset>
        <section>
            <p>1</p>
            <p>2</p>
            <p>3</p>
            <p>4</p>
            <p>5</p>
            <p>6</p>
        </section>
        <section>
            <p>1</p>
            <p>2</p>
            <p>3</p>
            <p>4</p>
            <p>5</p>
            <p>6</p>
        </section>
    </body>
</html>
